A software defined network (SDN) is now a novel network innovative architecture. Because the firmware of a traditional network device (switch and router) is locked and managed by a device manufacturer, SDN hopes to separate network management from physical network topology so as to release the network architecture from the limit of the hardware. In this way, a user can modify the network architecture like upgrading and installing software to meet the requirement of adjusting, expanding or upgrading the entire network architecture for enterprises. However, the underlying device on the data layer, such as hardware of switch, router, etc., does not need to be replaced, thereby greatly shortening the iteration cycle of the network architecture while saving much cost, so as to provide a good platform for innovation of core networks and applications.
Open vSwitch is an open virtual switch, completely supports the SDN architecture based on openflow protocol, and is an industry-recognized virtual switch which is the most mainstream for SDN. It is a product-quality multilayer virtual switching standard under the Apache 2.0 license. Open vSwitch has lower cost and higher working efficiency compared with a physical switch. One virtual switch can have dozens of ports to connect a virtual machine, while Open vSwitch itself occupies very small resources. The user can conduct flexible configuration according to his preference, and can receive and analyze a data packet.
Open vSwitch provides a traffic control function, but currently only supports htb mode and hfsc mode. For some occasions having real-time data transmission requirement, it is difficult for the two traffic control modes supported currently to meet the requirement. For example, a profinet network and an IEC61850 network widely used currently require the connected switch to support 802.1p, i.e., to forward the data packet based on the priority according to the information carried by pcp byte in an MAC layer of the data packet. Therefore, to enhance the traffic control function of Open vSwitch and to apply Open vSwitch to more occasions (e.g., in an industrial network), a priority-based forwarding mode for traffic control shall be added so as to support 802.1p for increasing the forwarding real-time performance of Open vSwitch.